II. Some insects go through distinct stages of egg, larva, pupa, adult (examples: butterflies; ants). d. Social insects

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1 Life Cycles and Insects Grade Level or Special Area: 2 nd grade Written by: Nancy Sales, The Classical Academy, Colorado Springs, Colorado Length of Unit: 13 lessons and a culminating activity (average lesson time: 55 minutes) I. ABSTRACT In this unit, the students will develop an understanding of life cycles and insects. They will study and observe a plant s life cycle, a chicken s life cycle, a frog s life cycle and a butterfly s life cycle. They will investigate common characteristics of insects and the effect they have on their environment, and they will explore ways that social insects are different from other insects. This unit is meant to cover the specific material required by the Core Knowledge Sequence for Life Cycles and Insects. This unit would be best taught in the late summer (August/September) or mid-spring (April/May). II. OVERVIEW A. Concept Objectives 1. Students will understand the processes of scientific investigation and conduct and communicate about such investigations. (Colorado State Science Standard #1) 2. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 3. Students will understand that science involves a particular way of knowing and understand common connections among scientific disciplines. (Colorado State Science Standard #6) B. Content from the Core Knowledge Sequence 1. Cycles in Nature (p. 59) a. Life Cycles i. The life cycle: birth, growth, reproduction, death ii. Reproduction in plants and animals a) From seed to seed with a plant b) From egg to egg with a chicken c) From frog to frog d) From butterfly to butterfly: metamorphosis 2. Insects (pp ) a. Insects can be helpful and harmful to people. i. Helpful: pollination; products like honey, beeswax, and silk; eat harmful insects ii. Harmful: destroy crops, trees, wooden buildings, clothes; carry disease; bite or sting b. Distinguishing characteristics i. Exoskeleton; chitin ii. Six legs and three body parts: head, thorax and abdomen iii. Most but not all insects have wings. c. Life cycles: metamorphosis i. Some insects look like miniature adults when born from eggs, and they molt to grow (examples: grasshopper; cricket). ii. d. Social insects Some insects go through distinct stages of egg, larva, pupa, adult (examples: butterflies; ants). 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 1

2 i. Most insects live solitary lives, but some are social (such as ants, honeybees, termites, wasps). ii. Ants: colonies iii. Honeybees: workers, drones, queen C. Skill Objectives 1. Students will be able to describe a life cycle. 2. Students will name the stages in a plant life cycle. 3. Students will make an observation chart recording the growth and development of a lima bean. 4. Students will describe the basic needs of a plant. 5. Students will make a model of a flower and label its parts. 6. Students will explain the purposes of the parts of the flower to a classmate. 7. Students will give examples of ways that flowers can be pollinated. 8. Students will name different ways that seeds are carried to new locations. 9. Students will make a model of a helicopter seed. 10. Students will plant a sunflower seed. 11. Students will sequence the stages of chicken development. 12. Students will make a model of chicken embryo development 13. Students will describe the life cycle of a chicken. 14. Students will observe and draw changes that occur in tadpoles as they grow. 15. Students will make flip books that represent stages in the life cycle of a frog and compare them with their own observations of a frog s life cycle. 16. Students will describe the life cycle of a frog. 17. Students will describe the life cycle of a butterfly. 18. Students will observe and examine the life cycle of a butterfly. 19. Students will participate in maintaining a classroom Metamorphosis Chart. 20. Students will make miniature butterflies. 21. Students will draw a model of the life cycles of a frog, chicken, butterfly and plant. 22. Students will discuss and recognize aspects of insects that can be helpful to man or harmful to man. 23. Students will give examples of how organisms interact with each other and with nonliving parts of their habitat. 24. Students will name the characteristics of insects and label their parts. 25. Students will make a model of an insect. 26. Students will name two types of growth models for insects. 27. Students will draw a model of an insect that undergoes complete metamorphosis and a model of an insect that undergoes incomplete metamorphosis. 28. Students will discover how more work can be done by a group than by an individual. 29. Students will discuss and draw aspects of social insects that make them different from other insects. 30. Students will compare a model of an insect with living insects. 31. Students will go on a hike in a tall grass or bushy area to collect their own insect specimens. III. BACKGROUND KNOWLEDGE A. For Teachers 1. Greenaway, Theresa. Plant Life, Cycles in Nature 2. Mound, Laurence. Insect, Eyewitness Books 3. Venn, Cecilia. Ants and Other Social Insects 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 2

3 B. For Students 1. The students will have prior knowledge of the water cycle (Core Knowledge 2 nd grade). 2. The students will have prior knowledge of what plants need to grow and basic parts of plants (Core Knowledge Kindergarten.). 3. The students should have some exposure to animal habitats and environments (Core Knowledge 1 st grade). IV. RESOURCES A. Brenner, Barbara. Thinking About Ants (Lesson Twelve) B. Bunting, Eve. Butterfly House (Lesson Seven) C. Chinery, Michael. Ant, Life Story (Lesson Twelve) D. Cox, Rosamund Kidman, and Cork, Barbara. Flowers (Lessons Three and Eight) E. Cyrus, Kurt. Oddhopper Opera, A Bug s Garden of Verses (Lesson Nine) F. Fleischman, Paul. Joyful Noise, Poems for Two Voices (Lesson Twelve) G. Gibbons, Gail. From Seed to Plant (Lesson Two) H. Heiligman, Deborah. From Caterpillar to Butterfly (Lesson Seven) I. Jeunesse, Gallimard. Bees. A First Discovery Book (Lesson Twelve) J. Jeunesse, Gallimard, and de Bourgoing, Pascale. The Egg (Lesson Five) K. McDonald, Megan. Insects Are My Life (Lesson Eleven) L. Milbourne, Anna. Tadpoles and Frogs, Usbourne Beginners (Lessons Six and Eight) M. Mound, Laurence. Insect, Eyewitness Books (Lessons Ten and Eleven) N. Parker, Nancy Winslow and Wright, Joan Richards. Bugs (Lesson Ten) O. Parker, Steve. Insects. Eyewitness Explorers (Lessons Ten and Eleven) P. Patchett, Fiona. Eggs and Chicks, Usbourne Beginners (Lessons Five and Eight) Q. Posada, Mia. Dandelions, Stars in the Grass (Lesson Four) R. Ross, Michael Elsohn. Life Cycles (Lesson One) S. Starosta, Paul. The Bee, Animal Close-Ups (Lesson Twelve) T. Unwin, Mike. Science with Plants (Lesson Four) U. Wallace, Karen. Born to Be a Butterfly, Dorling Kindersley Readers (Lessons Seven and Eight) V. What Your Second Grader Needs to Know, Revised Edition V. LESSONS Lesson One: The Merry-Go-Round of Life (approximately 60 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) The life cycle: birth, growth, reproduction, death 3. Skill Objective(s) a. Students will be able to describe a life cycle. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. Life Cycle Wheel (Appendix B) only teacher copy needed, but an enlarged reproduction of this would be best possibly on colored paper 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 3

4 3. Pictures of creatures at various stages of development to place on the life cycle wheel (optional) 4. Life Cycles by Michael Elsohn Ross C. Key Vocabulary 1. Life cycle: a repeating process of birth, growth, reproduction and death that occurs among every living species 2. Reproduce: to make babies of the same species D. Procedures/Activities 1. PLAN AHEAD!! BEFORE beginning this unit, be sure to order tadpoles, caterpillars, and fertilized chicken eggs. See Appendix D for supplies to pre-order and resources for ordering. See Appendix I for calendar for help in planning. 2. Introduce the Life Cycle Sound-off (Appendix A) and assign a part to be recited daily by each student in the class. Say Life Cycle Sound Off and the person who is assigned the first part should recite (or read) his part aloud, followed automatically by #2, #3, #4, etc. You may help them with pronunciations, but do not spend a lot of time on defining the terms right now. This gives them continuous exposure to the material that they will be tested on and it is FUN to do. (You can save this to go into a unit folder that will be compiled at the end of the unit for the student to keep and possibly for a grade.) 3. Hold up a picture of a Merry-Go-Round or a bicycle wheel. Explain that it turns and you really cannot find the beginning or the end. A cycle goes around and around without a beginning or end constantly returning to the place it started. 4. Using a model (Appendix B) that is labeled with the four stages (birth, growth, reproduction and death) explain the life cycle and its parts. Speak first about the human life cycle... baby, child, teenager, adult (reproduction), death. Define reproduce. Point to the stages in the model that represent each part of the cycle as you orally review the life cycle stages of a variety of creatures. Example robin: egg, baby bird, adult bird, egg. (If you have clip art or pictures of these stages, it would be good to place a picture of each stage over the words on the wheel). Emphasize the repeating pattern of the cycle. 5. Read Life Cycles to the students. 6. Ask the students what they have learned. E. Assessment/Evaluation 1. Allow students to act out the life cycle stages of a variety of creatures. Discuss as students perform. (i.e. Let s demonstrate the life cycle of a human. First, what does a baby look like? Then wait until they lay on the floor and kick and cry. What does a child look like? What does a teenager look like? What does an adult look like?) You may choose to have them act out other common life cycles or try it again after they study plants, frogs, chickens and butterflies. 2. Have students narrate back the definition for the terms life cycle and reproduce. (If you used pictures, students may want to have an opportunity to lay the clip art or pictures over the stage of life that is represented by each.) 3. Written assessment on this material occurs after Lesson Four. Lesson Two: Plant Life Cycle (approximately 50 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the processes of scientific investigation and conduct and communicate about such investigations. (Colorado State Science Standard #1) 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 4

5 b. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) Reproduction in plants and animals 1) From seed to seed with a plant 3. Skill Objective(s) a. Students will name the stages in a plant life cycle. b. Students will make an observation chart recording the growth and development of a lima bean. c. Students will describe the basic needs of a plant. d. Students will describe the life cycle of a plant. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. From Seed to Plant, by Gail Gibbons 3. Plastic zip-lock sandwich baggies one for each student 4. Masking tape or labels for the baggies 5. Cotton balls or squares 6. Dried lima beans or lima bean seeds enough for each student 7. Seed Germination Chart (Appendix C) C. Key Vocabulary 1. Pollen: tiny dust-like particles that are produced by the anthers in the male part of a flower 2. Pollination: when pollen travels from the anthers of one flower to the stigma of another flower for reproduction 3. Germination: when a seed begins to grow roots and sprout a stem 4. Fertilization: when the male part of a plant travels to the female part of a plant and combines to cause a seed to develop 5. Embryo: the undeveloped plant contained in a seed D. Procedures/Activities 1. Say Life Cycle and Insect Sound Off. The student who is assigned to say the first line should stand and begin reciting (or reading) his line. Student #2, #3, #4,.etc. should continue the Sound Off until all have finished reciting. 2. Read From Seed to Plant to/with the class (I have enough copies for each student to read along). Discuss and review the life cycle of a plant (seed, germination, growth, flower, pollination and seed). 3. Review vocabulary words. 4. Gather students around you as you sit on the floor. Take a lima bean and scratch off some of the seed coat so you can break the bean in two. Show the children the embryo part of the plant. Explain the part that will become a root and show the beginnings of the leaves. (The seed embryo is shown in the book.) Ask students what it will take for this seed to grow into a plant? (water, sunlight, etc.) 5. Explain to students that scientists like to record their observations so that they can learn from them. Tell them that they will be scientists today and will prepare a Seed Germination Chart. 6. First, give each child a baggie, a label, a cotton square, and a lima bean. Have them label the baggies and wet the cotton square (not dripping wet, but it must be fully soaked). They can insert the bean into the baggie on top of the cotton square and seal the zip lock baggie. 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 5

6 7. Have them write their names on the baggies and tape them to or near a window. 8. Hand out Seed Germination Chart (Appendix C). Students should complete the first part of the Seed Germination Chart including today s date. Every two or three days they will complete another line on the Seed Germination Chart. (I usually have students do this as a part of their morning activities before they get settled for the day, or during recess.) Save the Seed Germination Chart to go into a unit folder that the student may keep. E. Assessment/Evaluation 1. Review the life cycle of a plant and ask what they have learned 2. After all of the charts have been completed (about two weeks), discuss the student s observations with them. a. What did they notice about how their seed germinated? (the root went down, the stem went up toward the light) b. Did it grow quickly? c. How much did it grow? d. Did everyone s seed grow at the same rate? e. What do you think made the difference? Lesson Three: Plant reproduction (approximately 50 minutes) A. Daily Objectives 1. Concept Objectives a. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 2. Lesson Content a. Cycles in Nature i. Life Cycles (p. 59) a) Reproduction in plants and animals 1) From Seed to Seed with a plant 3. Skill Objective(s) a. Students will make a model of a flower and label its parts. b. Students will explain the purposes of the parts of the flower to a classmate. c. Students will give examples of ways that flowers can be pollinated. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. 8 ½ by 11 cardstock weight paper enough for each student 3. A full packet of colored tissue paper 4. A set of flower parts (Appendix E) for each student (copy Appendix E-Part 1 on green; copy Appendix E-Part 2 on yellow there are six sets of each per page and they will need to be cut apart before they are handed out) 5. Black yarn a piece about 2 feet long for each student 6. Model of labeled flower that you have made for students to reference 7. Transparency of the vocabulary words and their definitions (Appendix F) 8. Flowers Usbourne book by R. Kidman Cox and B. Cork C. Key Vocabulary 1. Stamen: the male, pollen producing reproductive part of a flower 2. Anther: the tip of a stamen that contains pollen 3. Pistil: contains the female parts of the flower 4. Stigma: the sticky tip of the pistil, is designed to collect pollen 5. Ovary: the bottom part of the pistil, will turn into a seed when fertilized 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 6

7 6. Sepals: the green petals that protect the inner parts of a bud until the bud opens 7. Petals: the colorful outer parts of the flower D. Procedures/Activities 1. Say Life Cycle and Insects Sound Off. Let students recite their parts. 2. Share some of the pictures out of the Flowers book. 3. Identify the reproductive parts of the flower and discuss their purposes. 4. Discuss ways that flowers can be pollinated. 5. Explain that you will be making a model of a flower and labeling its parts. (It is best to make one ahead of time to display for reference.) Begin by giving each student a cardstock paper, piece of colored tissue, flower parts (Appendix E), and the piece of black yarn. Have them draw a large flower blossom with a pencil on the cardstock. Cut and glue colored tissue to the outline to represent the petals. Cut and glue on the pistil and the stamens around it. The sepals should be cut out and glued on the base of the flower petals. 6. Display the pre-typed vocabulary word transparency (Appendix F). Before the students label the parts, tell them to get a partner and take turns naming the parts and explaining their purposes. They may use the words on the transparency to help them remember the names. Be sure to have a labeled model of the flower available for them to look at. 7. Have students write the names of the parts around the edges of the paper and cut pieces of the black yarn as pointer lines. Let pictures dry and display them on a bulletin board. E. Assessment/Evaluation 1. Use the first part of the Sound Off (the parts about the life cycle and about plant reproduction) to formulate oral questions for students to answer aloud. This is an informal assessment for which grades will not be kept. A written test over this material is provided in Lesson Four. Lesson Four: Traveling Seeds (approximately 45 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) Reproduction in plants and animals 1) From Seed to Seed with a plant 3. Skill Objective(s) a. Students will name different ways that seeds are carried to new locations. b. Students will make a model of a helicopter seed. c. Students will plant a sunflower seed. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. Packet of sunflower seeds two for each student 3. Styrofoam or paper cups one for each student 4. Enough potting soil to fill a cup for each student 5. Box lid or newspaper to keep soil mess contained 6. Strips of construction paper cut ¾ x 2 ½ one for each student 7. Science with Plants, Usbourne book by Mike Unwin (pp ) 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 7

8 8. Plants Quiz (Appendix G) one for each student 9. Dandelions, Stars in the Grass by Mia Posada C. Key Vocabulary 1. Burr: a prickly seed containing tiny hooks 2. Parachute: a seed that catches the wind like a parachute and blows away 3. Helicopter: a seed that has wings that cause it to spin like a helicopter 4. Hitchhiker: a seed with little barbs that cause it to get stuck in fur or clothing D. Procedures/Activities 1. Life Cycle and Insect Sound Off. It should be going faster by now. Immediately following the Sound Off, ask a few questions over older material for repetition and review. 2. If possible, take a hike through some weeds. Observe any flowers or seed pods. Have students collect any stickers that cling to their clothing. 3. Return to the classroom and ask: Why do seeds stick to our clothing? (So they can possibly drop off somewhere far from the mother plant.) How does it benefit the plant species for its seed to drop far from the original plant? (It doesn t have to compete for soil and water and sun so more of the seeds should survive.) 4. Read pages 16 and 17 of Science with Plants to the students and discuss the different ways that seeds travel in mud stuck on things; by hitchhiking (burrs and other stickers); wind (parachutes and helicopters); through animal droppings; some even float on the water. 5. Make a helicopter by making a 1 slit lengthwise down the cut strips of paper. Fold the cut pieces flat toward opposite sides of the paper. Your model should look like a T when held sideways. Toss it in the air and watch it flutter away. 6. After each child finishes his model, he should pick up a cup and write his name and the date on it. Then fill it with soil (over a box lid or newspaper). Each student should take two sunflower seeds and push them about an inch deep into the soil. Then water it! Put them near a window to be cared for (make it the child s responsibility) and observed and, later, taken home as a gift to Mom. 7. Ask students what they have learned. 8. (Extension/Literature connection) Read Dandelions, Stars in the Grass to the students. Have students write a couple of paragraphs in first person telling about what a seed might see on its journey to find a place to plant itself. They will first need to know what type of a seed they are and the most likely method of travel that type of seed might make. ( i.e. Here I sit in my spiney pod. It is fall now and I am very cold. A squirrel is coming near and romps close to me. Oops! I am being pulled away from the dried leaves that make my home. I am stuck in the squirrel s fur! He does not know it yet. etc.) E. Assessment/Evaluation 1. Be sure to do some oral review using the first six statements from the Sound Off before giving the written Plants Quiz (Appendix G). 2. Administer Plants Quiz (Appendix G). Save it to go into the unit folder that the student may keep. 3. Grade Quiz using answer sheet (Appendix H) Lesson Five: The Chicken or the Egg? (approximately 45 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 8

9 b. Students will understand that science involves a particular way of knowing and understand common connections among scientific disciplines. (Colorado State Science Standard #6) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) Reproduction in plants and animals 1) From egg to egg with a chicken 3. Skill Objective(s) a. Students will sequence the stages of chicken development. b. Students will make a model of chicken embryo development c. Students will describe the life cycle of a chicken. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. The Egg, by Gallimard Jeunesse and Pascale de Bourgoing; or Eggs and Chicks, Usbourne Beginners by Fiona Patchett (OR another good picture book that shows chicken embryo development (see Bibliography) 3. Appendix J Layered model of egg embryo development 4. Three brads per student 5. Appendix K Sequence cut and paste model of chicken development 6. Egg incubator 7. Fertilized chicken eggs (these should already be in the incubator) 8. High intensity lamp C. Key Vocabulary 1. Embryo: a chicken in an early stage of development before hatching 2. Egg tooth: the part of a chick s beak that it uses to break through the egg when hatching D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. (Per Appendix I, this would have been done when eggs first arrived, also.) Inform students that you will be learning about the life cycle of a chicken. Take a moment to look at a chicken egg under a high intensity lamp. Discuss any observable progress in the egg s development. Ask students, What is happening inside those eggs? 3. Read The Egg, or Eggs and Chicks to the students, emphasizing the pictures that show embryo development inside the egg. Also, emphasize the term embryo and egg tooth so that students will understand the vocabulary words. Remind students that a chicken embryo takes 21 days to grow before it is ready to hatch. 4. Ask students to think about the stages in a life cycle (birth, growth, reproduction and death). Can they name stages in the life cycle of a chicken? (egg, embryo, chick, adult chicken, egg) 5. Hand out the Appendix K and allow students to cut and paste the chicken s life cycle stages into the life cycle chart. Save this to go into a unit folder that you will compile at the end for the student to keep. 6. Finally, hand out Appendix J for students to color and layer a model of a chicken embryo. 7. When chicken eggs hatch, be sure to observe the chick s egg tooth. Look inside the eggshell. Did the chick break through the air pocket membrane? What other signs may there be that a chick lived there? 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 9

10 E. Assessment/Evaluation 1. Check Appendix K to see if students were able to sequence the stages of the chicken s life cycle correctly. 2. A written assessment of this material will be given in Lesson Nine. Lesson Six: From Egg to Frog (approximately 45 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) b. Student will understand that science involves a particular way of knowing and understand common connections among scientific disciplines. (Colorado Science Standard 6) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) From frog to frog 3. Skill Objective(s) a. Students will observe and draw changes that occur in tadpoles as they grow. b. Students will make flip books that represent stages in the life cycle of a frog and compare them with their own observations of a frog s life cycle. c. Students will describe the life cycle of a frog. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. Flip books one for each student (see Appendix L for model; this is a booklet with graduated sized pages, held together by plastic comb binding at the top; the cover measures 3 ½ x 6 ; page 2 = 4 x 6 ; page 3 = 4 ½ x 6 ; page 4 = 5 x 6 ; page 5 = 5 ½ x 6 ; pages 6-9 and the back cover = 6 x 6 ; when these are stacked together and bound from the top, each page emerges ½ longer than the page before it) (these should be pre-made and would have been distributed when the tadpoles arrived according to the calendar in Appendix I) 3. Tadpoles and Frogs, Usbourne Beginners Series, by Anna Milbourne (these are easy readers, so it would be good to have one per child, if possible) (another book with great pictures of the stages in a frog s life cycle would be acceptable) 4. Fish tank 5. Live tadpoles (see Appendix D these should have been pre-ordered) C. Key Vocabulary 1. Amphibian: an animal that can live on land and in water 2. Gill: an opening on the side of a frog s body that helps it to breathe under water 3. Tadpole: a baby frog; a fish-like creature that will grow legs and change into a frog D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. Take students to the fish tank to observe the tadpoles. Ask, What do you see, what do you notice? Discuss the observation drawings that they have already begun in the backs of their flip books, emphasizing the stages in the frog life cycle that they have observed. 3. Read Tadpoles and Frogs with the students, emphasizing the vocabulary above. 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 10

11 4. Have students get out their flip books. Complete the writing in the books. Students can finish drawing and coloring the pictures in their spare time. The books will look much nicer if students use a ruler to draw their writing lines before they start the writing. Two lines per page should be enough. Write the following on each page: a. Frogs begin life as jelly-like eggs floating in water. Bottom label: egg b. A tadpole hatches from each egg. Bottom label: tadpole c. The tadpoles begin to grow hind legs. Bottom label: hind legs d. Front legs begin to grow as their tail shrinks. Bottom label: front legs e. Finally they have become tiny adult frogs. Bottom label: adult frogs 5. Review Ask students to name the stages in a frog s life cycle. 6. Art Extension: Have students make folded paper chain frogs. (Cut ½ off of the length of 11 x 17 paper, then cut into thirds lengthwise strips should be just under 3 wide. Accordion fold the paper 1 ½ apart. Then draw half of a frog against one of the folds and cut them like you would paper dolls. Unfold to see a paper chain of frogs!) E. Assessment/Evaluation 1. The flip books can be used as an assessment when they are completed. They should have appropriate drawings in them that indicate an understanding of the life cycle stage that they illustrated. 2. A written assessment over this material will be given in Lesson Nine. Lesson Seven: Flutter by, Butterfly! (approximately 45 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the processes of scientific investigation and design, conduct, communicate about, and evaluate such investigations. (Colorado Science Standard 1) b. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado State Science Standard #3) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) From butterfly to butterfly (metamorphosis) 3. Skill Objective(s) a. Students will describe the life cycle of a butterfly. b. Students will observe and examine the life cycle of a butterfly. c. Students will participate in maintaining a classroom Metamorphosis Chart. d. Students will make miniature butterflies. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. From Caterpillar to Butterfly by Deborah Heiligman (read together or one per student; this book is specifically about the Painted Lady butterfly, the same type 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 11

12 of caterpillar that we order); OR Born to be a Butterfly by Karen Wallace (read together or one per student) 3. Spring-loaded clothespins one per student 4. Coffee filters one per student 5. Pipe cleaners one per student 6. Water-based student markers 7. Newspaper or paper towels 8. Hot glue gun (optional) 9. Small pan of water or spray bottle 10. Metamorphosis Chart (Appendix M) enlarged for classroom use 11. Butterfly House by Eve Bunting C. Key Vocabulary 1. Metamorphosis: to change from one form to another 2. Caterpillar: the larva (worm-like) stage of a butterfly 3. Chrysalis: the pupa (hard-shelled covering) stage of the butterfly 4. Proboscis: the long, straw-like tongue of a butterfly D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. Ask students if they have ever seen a chrysalis or a cocoon. Did they know what was inside? (Either a moth or a butterfly.) A chrysalis is the hard, smooth cocoon. The fuzzy or silk types are usually just referred to as cocoons. Explain that we are now going to explore the life cycle of a butterfly. 3. Read From Caterpillar to Butterfly. Review the life cycle stages (egg, caterpillar, chrysalis, adult butterfly). Explain the term metamorphosis and that other insects also metamorphose. (ladybugs, flies, ants and bees) The key word to remember is change. 4. Show students the Metamorphosis Chart (Appendix M). You will have already begun this chart on the day the caterpillars arrived according to the calendar in Appendix I. Which life cycle stages have your caterpillars already experienced? 5. Finally, make a butterfly to hang in the classroom. Hand out coffee filters. Students should write their names very small along the edge of the coffee filter with a sharpened pencil or ink pen (so it won t run when it gets wet). Using water-based markers, have each student color the coffee filter. These will become the wings of a caterpillar. Lay out the filters on newspaper and spray them with water; OR, dip them quickly into a pan of water and lay them out. Allow them to dry. 6. After they have dried, accordion-fold each one and clip them in the middle with a clothespin. (You may want to straighten them out a little after they are clipped.) Shape the pipe cleaner into a V and curve them to look like antennae. Clip the middle of the V to the outer-most part of the clothespin clip above the folded coffee filter. (You may want to hot glue them to the place where the clothespin clip closes to make sure that they stay.) Hang these around the room! 7. (Extension/Literature connection) Read Butterfly House to the students. Discuss the book and the Painted Lady butterfly. For a writing assignment, have students tell about a time when they did a special project or something fun with a grandparent or other family member. Ask them to tell what made it so special. E. Assessment/Evaluation. 1. Allow students to act out the life cycle stages of a variety of creatures. Discuss as students perform. (i.e. Let s demonstrate the life cycle of a human. First, what does a baby look like? Then wait until they lay on the floor and kick and 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 12

13 cry. What does a child look like? What does a teenager look like? What does an adult look like?) You may choose to have them act out other common life cycles or try it again after they study plants, frogs, chickens and butterflies. 2. Ask review questions based on recitation lines from the Sound Off (Statements 1-10). 3. A written assessment covering this material will be given in Lesson Nine. Lesson Eight: Four Different Life Cycles (approximately 60 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will know and understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado Science Standard 3) b. Students will understand that science involves a particular way of knowing and understand common connections among scientific disciplines. (Colorado Science Standard 6) 2. Lesson Content a. Cycles in Nature (p. 59) i. Life Cycles a) The life cycle: birth, growth, reproduction and death b) Reproduction in plants and animals 1) From seed to seed with a plant 2) From egg to egg with a chicken 3) From frog to frog 4) From butterfly to butterfly: metamorphosis 3. Skill Objective(s) a. Students will draw a model of the life cycles of a frog, chicken, butterfly and plant. B. Materials 1. Life Cycle and Insects Sound Off (Appendix A) one copy for each student 2. Life cycle words for Group Up game (Appendix N) cut apart before the game 3. Life cycle drawing page (Appendix O) one for each student 4. Books that have awesome pictures of a frog, chicken, plant and butterfly life cycle a. Born to Be a Butterfly, a Dorling Kindersley Reader, by Karen Wallace b. Eggs and Chicks, Usborne Beginners, by Fiona Patchett c. Flowers, Usborne Nature Book, by Rosamund Kidman Cox and Barbara Cork d. Tadpoles and Frogs, Usborne Beginners, by Anna Milbourne 5. One copy of Appendix P to aid the teacher in presenting lesson C. Key Vocabulary 1. Germination: when a seed begins to grow roots and sprout a stem 2. Reproduction: the process of making babies of the same species 3. Pollination: when pollen travels from the anthers of one flower to the stigma of another flower for reproduction 4. Embryo: the undeveloped plant contained in a seed 5. Tadpole: a baby frog; a fish-like creature that will grow legs and change into a frog 6. Caterpillar: the larva (worm-like) stage of a butterfly 7. Chrysalis: the pupa (hard-shelled covering) stage of the butterfly 8. Metamorphosis: to change from one form to another 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 13

14 D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. Hand out life cycle drawing page (Appendix O) to each student. Ask, Who can narrate to me the life cycle of a plant? While the student explains, draw the cycle on the board in a circular format. Draw a seed at the top, then down and to the right a germinated seed, then down and to the left an adult plant, then up and to the left some bees on the flower of the plant (representing reproduction). Draw in arrows between each stage to demonstrate the circular pattern of the cycle. Have students make a similar drawing on the Seed section of their papers. Use pictures from the book Flowers to aid in explaining and to use to help draw each stage. 3. Do the same thing with the other three life cycles (chicken, frog, butterfly). See sample in Appendix P. Use pictures from the books to aid in presenting the lesson. Students may color these and turn them in to be compiled into a unit book which may be graded or for them to take home. E. Assessment/Evaluation 1. Students will play a Group Up game that will demonstrate their knowledge of life cycles. Cut out the words from Appendix N. This is an informal assessment. To play the Group Up game: The way to play this is to have students come to an open area in the room where they will mill around without speaking or touching each other. After they can do that successfully, hand out the word slips. Students will have to group up with others whose words go with the word they are holding. Tell them, These are the groups: life cycle of any living thing; parts of a plant; plant cycle; frog cycle; butterfly cycle; chicken cycle.) NO talking! After they look at their words and think about the group they should be in, say, Group Up. Students will show their words to one another and through gestures they may decide to group up, then they will look for others to join the group. After a minute or so, have students stop and make sure that they grouped up correctly. If a child is in the wrong group, give him a chance to change to a different group. Ask someone to give a label to the groups. i.e. parts of a plant ; or life cycle of a frog ; or life cycle of any living thing. The words they are holding in each group should all go together. Then, have them trade words and go again. 2. A written quiz over this material will be given at the beginning of Lesson Nine. Lesson Nine: Helpful and Harmful Insects (45 minutes) A. Daily Objectives 1. Concept Objective(s) Students will know and understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado Science Standard 3.) 2. Lesson Content a. Insects (p. 59) i. Insects can be helpful and harmful to people. a) Helpful: pollination; products like honey, beeswax, and silk; eat harmful insects b) Harmful: destroy crops, trees, wooden buildings, clothes; carry disease; bite or sting 3. Skill Objective(s) a. Students will discuss aspects of insects that can be helpful to man or harmful to man. 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 14

15 b. Students will give examples of how organisms interact with each other and with nonliving parts of their habitat. B. Materials 1. Life Cycles Quiz (Appendix Q) one for each student 2. Helpful/Harmful Chart (Appendix R) one for each student 3. Poster or pictures of a variety of insects (those that can be helpful bees and silkworms, and those that can be harmful termites or bees) 4. Oddhopper Opera by Kurt Cyrus C. Key Vocabulary 1. Decompose the breakdown of dead plants or animals into simpler forms of matter; to rot or decay D. Procedures/Activities 1. Begin by holding a review from the Sound Off statements 1-10, 13. Ask questions related to the Sound Off. Then, hand out the Life Cycles Quiz (Appendix Q) for students to work. 2. After the quiz has been turned in, hold up the poster or pictures of some insects. Have students identify the types of insects aloud. 3. Ask students, When you look at this insect, what do you think? Do you have positive or negative feelings about this insect? Why? Explain that insects can be both helpful and harmful to man and that our feelings may reflect our own experiences with them (i.e. a bee stings but it also gives us honey). 4. Pass out the Helpful/Harmful Chart (Appendix R). Lead a discussion and listing of ways that insects can be helpful (silk, honey, beeswax, eat other insects, pollinate plants, become food of other creatures (birds), help other plants/animals to decompose). (Students may draw pictures on this page also.) Ask students which one they think may be the most important. Discuss the fact that if plants did not get pollinated they would not reproduce; then many other forms of life on earth might eventually cease to exist since many animals (including man) feed on different types of plants. 5. Discuss and list ways in which insects can be harmful to man (damage crops and trees, damage buildings, damage clothing, bite or sting, carry disease). 6. (Extension/Literature connection) Read Oddhopper Opera, A Bug s Garden of Verses, a fun, lyrical book about garden living for creepy crawlies. This can be an introduction to a poetry lesson or just a fun read. E. Assessment/Evaluation 1. A written quiz will be given in Lesson Thirteen. Lesson Ten: Characteristics of Insects (approximately 50 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will know and understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. 2. Lesson Content a. Insects (p. 59) i. Distinguishing characteristics a) Exoskeleton; chitin b) Six legs and three body parts: head, thorax and abdomen c) Most but not all insects have wings 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 15

16 3. Skill Objective(s) a. Students will name the characteristics of insects and label their parts. b. Students will make a model of an insect. B. Materials 1. Sound Off (Appendix A) one for each student 2. Characteristics of Insects worksheet (Appendix S) one for each student 3. Make a transparency of Characteristics of Insects worksheet (Appendix S) one copy 4. Completed sample of Characteristics of Insects worksheet (Appendix U) 5. Group Up words for game (Appendix T); these should be cut apart before the game 6. Egg cartons sectioned into four parts three egg cups per part you will need one of these for each student 7. Pipe cleaners 8. Colored paper (optional) 9. Insects by Steven Parker (Dorling Kindersley); or Insect by Laurence Mound (Eyewitness Books) 10. Bugs by Nancy Winslow Parker and Joan Richards Wright C. Key Vocabulary 1. Invertebrate: a classification for a group of animals that have no backbone 2. Arthropod: a classification of invertebrates that have an exoskeleton and jointed legs 3. Thorax: the middle section of an insect; its legs and wings protrude from the thorax 4. Abdomen: the end section of an insect 5. Exoskeleton: the outside supportive covering of an arthropod 6. Chitin: a substance that forms the hard outer coating of many insects and arthropods D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. Show pictures of insects from one of the Insect books. Have students name other insects. Ask the students to look closely at the pictures. What do they notice about insects? What are things that all insects have in common? All insects have a head, thorax, abdomen, exoskeleton and six legs. Most insects have wings. The exoskeleton is made out of a material called chitin. 3. What about spiders? Explain that spiders are not insects. Explain that scientists group animals according to their similarities. Both spiders and insects are invertebrates and spiders and insects are both in a grouping of animals called arthropods. Explain. Also in the group are crustaceans, centipedes and millipedes. However, spiders have eight legs and insects have only six. 4. Hand out Characteristics of Insects worksheet. Have students draw an ant or other insect with easily identifiable body parts. (You may want to make an overhead of this page and model the drawing of the insect while you discuss the parts). See sample (Appendix U). Show lots of pictures from the books while pointing out the distinguishing characteristics. 5. Have students keep the worksheets in a folder to finish another day. 6. Make models of insects using segments of egg carton. Put pipe cleaner antennae on the head. All six legs (made of pipe cleaners or paper) should protrude from the thorax or middle section. If the student wishes to add wings made from paper, they should protrude from the back of the thorax, also. Be as 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 16

17 creative as you like with these. The egg cartons can be painted or colored with markers before adding the legs, wings or antennae. Be sure to emphasize proper vocabulary when you discuss the exoskeleton made of chitin, etc. Display completed models around the room. 7. (Extension/Literature connection) Read Bugs by Nancy Winslow Parker and Joan Richards Wright. See if students can think of the name of the bug that rhymes with the last word in each sentence before you tell them the name of it. E. Assessment/Evaluation 1. A properly made model with all its parts can serve as an assessment. 2. Play the Group Up game using Appendix T words (See Lesson Eight Assessment section for directions to play). The groups in this set should be identified as: characteristics of an insect; ways insects are helpful; ways insects are harmful. Lesson Eleven: Two Kinds of Metamorphosis (approximately 45 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will know and understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado Science Standard 3) 2. Lesson Content a. Insects (p. 59) i. Life cycles: metamorphosis a) Some insects look like miniature adults when born from eggs, and they molt to grow (examples: grasshopper; cricket). b) Some insects go through distinct stages of egg, larva, pupa, adult (examples: butterflies; ants) 3. Skills Objective(s) a. Students will name two types of growth models for insects. b. Students will draw a model of an insect that undergoes complete metamorphosis and a model of an insect that undergoes incomplete metamorphosis. B. Materials 1. Sound Off (Appendix A) one for each student 2. Characteristics of Insects worksheet (Appendix S) one for each student from Lesson Ten 3. Transparency of Characteristics of Insects worksheet (Appendix S) from Lesson Ten 4. Completed sample of Characteristics of Insects worksheet (Appendix U) 5. Insects by Steve Parker (Dorling Kindersley) pp ; or Insect by Laurence Mound (Eyewitness Books) pp Insects Are My Life by Megan McDonald C. Key Vocabulary 1. Complete metamorphosis: profound changes in body form or appearance in an insect (egg, larva, pupa, adult) 2. Incomplete metamorphosis: changes due mostly to growth in the insect 3. molt: the process of shedding the outer skin as an insect grows 4. nymph: the infant or immature stage of an insect that undergoes incomplete metamorphosis 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 17

18 D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. Using one of the Insect books, explain complete metamorphosis and incomplete metamorphosis. Name a variety of insects that undergo complete metamorphosis (i.e. butterflies, moths, ants, bees, lady bugs) and a variety of insects that undergo incomplete metamorphosis (grasshoppers, crickets, dragonflies). 3. Have students get out their Characteristics of Insects worksheet (Appendix S). Using the transparency for the worksheet, draw a model of a life cycle that demonstrates complete metamorphosis (egg, larva, pupa, adult) and one that demonstrates incomplete metamorphosis (egg, infant (or nymph), adult). See sample (Appendix U). When they are finished, have them put them away in a folder for one last lesson. 4. (Extension/Literature connection) Read Insects Are My Life. Discuss what the title means (i.e. Insects are my passion). Ask students if they have a passion. This could also become a writing exercise is my life. Or have students do a charade demonstrating their passion for other students to guess. This could also be a character lesson about showing respect to those whose passions are different than our own. E. Assessment/Evaluation 1. A written quiz will be given in Lesson Thirteen. Lesson Twelve: Social Insects (approximately 55 minutes) A. Daily Objectives 1. Concept Objective(s) a. Students will understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado Science Standard 3) 2. Lesson Content a. Insects (p ) i. Social Insects a) Most insects live solitary lives, but some are social (such as ants, honeybees, termites, wasps). b) Ants: colonies c) Honeybees: workers, drones, queen 3. Skill Objective(s) a. Students will discover how more work can be done by a group than by an individual. b. Students will discuss and draw aspects of social insects that make them different from other insects. B. Materials 1. Sound Off (Appendix A) one for each student 2. Characteristics of Insects worksheet (Appendix S) one for each student from Lesson Ten 3. Transparency of Characteristics of Insects worksheet (Appendix S) from Lesson Ten 4. Completed sample of Characteristics of Insects worksheet (Appendix U) 5. The Bee, Animal Close-Ups by Paul Starosta; or Bees by Gallimard Jeunesse 6. Ant, Life Story by Michael Chinery, or Thinking About Ants by Barbara Brenner 7. Honeybees, from Joyful Noise, Poems for Two Voices, by Paul Fleischman type this out and distribute a copy to each student for choral reading 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 18

19 C. Key Vocabulary 1. Social insects: insects that live in communities and work together and depend on each other for their survival 2. Community: a grouping of insects, like a large family or neighborhood 3. Queen: the egg-layer in a social insect community, there is usually only one queen 4. Worker: in a social insect community they do many different jobs such as caring for eggs, cleaning the nest/hive, gathering food 5. Drone: male bees that mate with the queen 6. Colony: an ant community D. Procedures/Activities 1. Say the Sound Off aloud together. Ask a few review questions formulated from the Sound Off. (See Lesson One for recitation procedures.) 2. Tell students that they are going to learn about another type of insect called a social insect. Explain the vocabulary social insect and community. 3. Begin with an activity that is designed to demonstrate how working together can produce more than working alone. Have four students stand in a row. They may use a small (Dixie-sized) cup to move water from a tub to another bucket about 10 feet away. Time them for one minute. After the minute, see who moved the most water and have the class observe how full the buckets became. Now, have them do the same thing, only do it fireman style by having them pass the cup along with one person moving the cup back to the beginning after they dump. There should be quite a bit more water moved in one minute. Have the class observe the difference in the amounts of water moved. 4. Have them get out their Characteristics of Insects worksheet (Appendix S) to make drawings in the Social Insects section. Model the drawing on the transparency of the same sheet. See sample (Appendix U). 5. Using The Bee explain the social order in the hive: the queen is the most important; she mates with the drones and is served by worker bees. Worker bees also take care of the eggs, larva and pupas; make wax cells; collect pollen and nectar to make honey; protect the hive. Bees can communicate with each other by leaving a scent in the air or by doing a dance. The dance will communicate where a lot of nectar or pollen has been located. 6. Explain that ants live in colonies. Using the book, Ant, Life Story, tell about aspects of ant life. Again, the queen is the most important and she is surrounded by worker ants that care for her, for the colony s nest, for the eggs, larva and pupa, that collect food, and that protect the nest from invaders. 7. When students have completed their drawings, they may turn in their Characteristics of Insects worksheet to be graded and entered into their unit folder. 8. Ask students to share what they have learned. 9. (Extension/Literature connection) Divide the class in two and assign each a part from the Honeybees poem out of Joyful Noise, Poems for Two Voices. Students enjoy reading this several times or again on different days. E. Assessment/Evaluation 1. A written quiz will be given in Lesson Thirteen. 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 19

20 Lesson Thirteen: Entomology (field trip may take a couple of hours) A. Daily Objectives 1. Concept Objective(s) a. Students understand the characteristics and structure of living things, the processes of life, and how living things interact with each other and their environment. (Colorado Science Standard 3) b. Students understand that science involves a particular way of knowing and understand common connections among scientific disciplines. (Colorado Science Standard 6) 2. Lesson Content a. Insects (p. 59) i. Distinguishing characteristics a) Exoskeleton; chitin b) Six legs and three body parts: head, thorax and abdomen c) Most but not all insects have wings 3. Skill Objective(s) a. Students will compare a model of an insect with living insects. b. Students will go on a hike in a tall grass or bushy area to collect their own insect specimens. B. Materials 1. Sound Off (Appendix A) one for each student 2. Insect nets or pillow cases (for collecting bugs stirred up in the brush or tall grass) one for each child or one for two children to share 3. Insects Quiz (Appendix V) one for each student 4. A white sheet--to distribute and look at collected insects on. 5. Bug observation jars (optional), or zip-lock baggies one for each student 6. Magnifying glasses (optional) 7. Insect Field Guide (optional) for identifying insects in various stages of development 8. Field, park or tall grassy area for hike C. Key Vocabulary No new vocabulary. Review all vocabulary. D. Procedures/Activities 1. Have students say the Sound Off (Appendix A) see Lesson One. 2. Find a tall grassy area (near water is the best) or bushy area. Give each student a net or pillow case and show them how to swish the net or pillow case down into and through the grass several times and in a couple of areas to stir up insects. Then they must hold the top closed and bring the insects and their nets to the white sheet. Shake out the insects on the white sheet. Choose some to put in jars or baggies for longer observation (Don t put insects with fragile wings in the baggies). 3. Identify body parts and name the insects characteristics. Differentiate between insects and spiders (arachnids). What common group do they come from? (Arthropods) 4. Name as many insects as you can. Identify different stages of growth (nymphs or egg, larva, pupa, adult). 5. Allow students to explore and discover insects! E. Assessment/Evaluation 1. Administer Insects Quiz (Appendix V). 2 nd Grade, Life Cycles and Insects 2003 Colorado Summer Writing Institute 20